Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Calculate how long filling your pool takes and what the water costs, from your pool's volume and fill rate.
Knowing your pool's volume (from the Pool Volume Calculator) is only half the planning picture -- this calculator answers the practical follow-up questions: how many hours will filling actually take at your hose or fill line's flow rate, and what will that water cost at your utility's rate.
Enter your pool's volume in gallons, your fill rate in gallons per hour (a standard garden hose delivers roughly 300-600 gallons per hour depending on water pressure and hose diameter), and your water utility's price per 1,000 gallons.
Fill Time (hours) = Gallons ÷ Fill Rate
Water Cost = (Gallons ÷ 1,000) × Price per 1,000 Gallons
This estimates the water bill only -- it doesn't include sewer charges some utilities apply even to water that doesn't return to the sewer system (worth checking, since some municipalities offer a "sewer credit" or separate meter for pool fills).
The fill rate is the input people most often guess wrong, and it drives the fill time result directly. A simple way to measure it is the bucket test: turn the hose on fully, time how long it takes to fill a bucket of known size, and convert. For instance, if a 5-gallon bucket fills in 30 seconds, that is 10 gallons per minute, or 600 gallons per hour. Do this at the hose end you will actually use, since attachments, splitters, and long or kinked hoses reduce flow.
Running two hoses from two separate spigots roughly adds their flows, which cuts fill time. Splitting one spigot into two hoses usually does not, because the spigot and the supply line are the limit. If you use several sources, add up the measured rates from each and enter the total.
Hypothetical example: an 18,000 gallon pool, one hose measured at 420 gal/hr, and a second hose on a separate spigot at 380 gal/hr. Combined rate 800 gal/hr. Fill time 18,000 / 800 = 22.5 hours. At an assumed price of $4.10 per 1,000 gallons, water cost is 18 x 4.10 = $73.80.
The cost figure reflects the water rate you enter. Many utilities use tiered pricing, where each block of usage costs more than the previous one. A large fill can push your bill into a higher tier, so the effective price per 1,000 gallons for that month may be above the base rate on your bill. If you know your tiers, enter a blended rate, or calculate the fill in parts at the different tier prices and add them.
A fill time of a day or more means the pool will be filling unattended. Check hoses periodically, and consider setting a timer or alarm so the water does not overflow. If you are on a private well, ask your well professional how long the pump can safely run continuously before starting a long fill. If the estimated cost seems high, ask your utility whether it has a program for pool fills, and confirm the rates with the utility itself, since they change.
Typically 300-600 gallons per hour depending on your home's water pressure and the hose's diameter -- a wider hose at good pressure fills noticeably faster than a standard narrow hose.
Many municipalities and well systems handle a slow, continuous fill better than an attempt to fill as fast as possible -- check your water pressure and well capacity (if applicable) before starting a large fill.
Time how long the hose takes to fill a container of known size, such as a 5-gallon bucket, then convert to gallons per hour. Test at the same spigot and hose length you will use.
Tiered water rates, sewer charges, and fixed fees are not part of a single per-1,000-gallon price. Check your bill for these items.
Only if they come from separate spigots with adequate supply. Two hoses on one spigot mostly share the same limited flow.
No. It calculates a single fill from the volume, rate, and price you enter.